Composite twisting and production method therefor, and woven fabric and knitted fabric using the composite twisting

ABSTRACT

A composite twist yarn is produced by twisting a spun yarn and at least one filament together. The composite twist yarn has features that the twisted direction of the composite twist yarn is substantially identical to the twisted direction of the spun yarn entwined in the composite twist yarn, and that the number of twists of the composite twist yarn is larger than that of the spun yarn entwined in the composite twist yarn. The composite twist yarn is produced by making a twisted spun yarn and at least one filament parallel to each other to a paralleled yarn, twisting the paralleled yarn in a direction reverse to the twisted direction of the spun yarn, and continuing the twisting over an untwisted point of the spun yarn.

TECHNICAL FIELD

[0001] The present invention relates to a novel composite twist yarn, aproduction method for composite twist yarn, and to a woven fabric and aknitted fabric using the composite twist yarn.

BACKGROUND ART

[0002] The following yarns are known as primary composite yarns in whichspun yarns and filaments are combined with each other:

[0003] (1) a core yarn constructed such that a cotton-like substance(lump of staples) covers a core yarn consisting of a filament orfilaments, and the entirety is twisted;

[0004] (2) a single-covered yarn (a double-covered yarn) constructedsuch that a single layer (a multi layer) of spun yarn is entwined arounda core yarn consisting of a filament or filaments; and

[0005] (3) a plied yarn constructed such that two or three spun yarnsand at least one (usually, one) filament are twisted with each other.

[0006] Among the above, the core yarn (1) has features that the spunyarn is exposed over the entirety of the core yarn, has a good texture,warm appearance and touch, and is categorized into a high-quality yarn.However, in producing the core yarn using a cotton spun yarn, it isrequired to secure a yarn strength by enhancing entwining of the fibers.Accordingly, it is desirable to use relatively long fibers exclusivelyas a material for the cotton spun yarn by sorting out and excludingrelatively short fibers, which may lead to an exceedingly low yield ofraw cotton or the like. Further, this method necessitates asophisticated technique and facility to cover the core part offilament(s) with the spun yarn, and accordingly may raise the cost of aresultant composite yarn. In addition, production of core yarns of afine count is extremely difficult in light of the constraint onproduction.

[0007] The covered yarn (2) is the one in which a spun yarn is entwinedaround the filament or filaments. The covered yarn has a great yarnstrength, good appearance and touch. However, since it is required toentwine a singe layer or a multi layer of the spun yarn around thefilament(s), productivity of the covered yarn (2) as a composite yarn islow.

[0008] Since the plied yarn (3) is usually produced by making two orthree spun yarns and a filament parallel to each other to a paralleledyarn, and twisting the paralleled yarn, sorting of raw cotton (removalof staples), which is required in production of the core yarn (1), isnot necessary, and hence productivity of the plied yarn (3) as acomposite yarn is high. Nevertheless, since the plied yarn (3) is theone in which the spun yarns and the filament are tightly twistedtogether, the plied yarn (3) has a stiff texture as a composite yarn andfails to provide a warm appearance and touch.

[0009] The present invention has been accomplished in view of the aboveproblems residing in the prior art. A first object of the presentinvention is to provide a composite twist yarn having an improvedtexture, superior (warm) appearance and touch by focusing on a pliedyarn that does not require sorting of raw cotton and is effective inproviding a high yield and productivity as a composite yarn, toestablish a novel method capable of easily producing such a compositetwist yarn even with a fine count, and to provide a woven and knittedfabric having a superior appearance and touch with use of such acomposite twist yarn.

[0010] Another object of the present invention is to provide atechnology that enables to easily produce, with use of a twistingfacility and at a low cost, a composite twist yarn which has asubstantially equivalent or superior quality to the expensive core yarnproduced by the conventional complex spinning facility.

DISCLOSURE OF THE INVENTION

[0011] An inventive composite twist yarn that solves the above problemsis a composite twist yarn comprising a spun yarn and at least onefilament, the spun yarn and the filament being twisted with each other,the twisted direction of the composite twist yarn being substantiallyidentical to the twisted direction of the spun yarn entwined in thecomposite twist yarn, and the number of twists of the composite twistyarn being larger than the number of twists of the spun yarn entwined inthe composite twist yarn.

[0012] Preferably, use of an elastic filament as the filament in thecomposite twist yarn is extremely advantageous in providing thecomposite twist yarn with an elasticity, as well as in terms ofappearance and touch.

[0013] Another aspect of the present invention is directed to a methodfor producing a composite twist yarn having the above superiorproperties. The method comprises making a twisted spun yarn and at leastone filament parallel to each other to a paralleled yarn, twisting theparalleled yarn in a direction reverse to the twisted direction of thespun yarn, and continuing the twisting in the reverse direction over anuntwisted point of the spun yarn.

[0014] The inventive composite twist yarn has a great yarn strength,superior texture, appearance, and touch. Accordingly, a woven fabric anda knitted fabric produced with use of at least part of the inventivecomposite twist yarn has also a superior texture, appearance, and touch.Such a woven fabric and a knitted fabric are embraced in the scope ofthe present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015]FIGS. 1 through 4 are illustrations showing a composite twist yarnand a method for producing the composite twist yarn according to anembodiment of the present invention.

[0016]FIG. 5 is an illustration explaining a relation between a changein a twisted direction and the number of twists with respect to a spunyarn and a paralleled yarn used as a raw material in implementing thepresent invention, wherein the spun yarn is denoted at B, and a filamentfor the paralleled yarn is denoted at M.

BEST MODE FOR CARRYING OUT THE INVENTION

[0017] In view of the above problems residing in the prior art, thepresent inventors have made a research and development from variousviewpoints concerning a composite twist yarn which has the merits of theplied yarn (3): no need of sorting of raw cotton, securing a high yield,and feasibility in production, which has overcome the demerits of theplied yarn: stiff texture, and poor appearance and touch, and which iscapable of producing a sophisticated woven and knitted fabric at a lowcost.

[0018] They have found that the conventional plied yarn is usuallyproduced by twisting two or three spun yarns and a filament together ina direction reverse to the twisted direction of the spun yarns, and thethus produced plied yarn has drawbacks such as a poor appearance and astiff touch because the plied yarn is twisted too much by the twistingof the spun yarns. In view of this, they have proceeded with a researchbased on an idea that the defects of the conventional plied yarn can beovercome by establishing a technique of entwining a spun yarn with afilament while suppressing undesired tightening of the twist yarn.

[0019] In the course of the research, they have come up with an ideathat undesired tightening of the spun yarn can be alleviated by atwisting process in which a single spun yarn and a filament are entwinedand twisted together in a direction reverse to the twisted direction ofthe spun yarn, because in such a twisting process, as the twisting isproceeded, the spun yarn is untwisted, whereas twisting two or more spunyarns and a filament together fails to solve the drawback inherent tothe conventional plied yarn because it is a usual practice to set thetwisted direction of the twist yarn reverse to the twisted direction ofthe spun yarn.

[0020] Twisting a spun yarn and a filament together in a directionreverse to the twisted direction of the spun yarn, however, eventuallyresults in untwisting of the spun yarn, and accordingly, fails tomaintain the strength as a composite twist yarn. Namely, twisting thespun yarn and the filament together in the reverse direction has alimitation of its own, and a composite twist yarn having a noticeablysuperior property to the conventional plied yarn was unable to obtainaccording to this method. Particularly, twisting a spun yarn in thereverse direction to such an extent as to nullify the twist of the spunyarn, namely, to render the twisted spun yarn to a substantiallyuntwisted state is not practically feasible in a twisting process forproducing a composite twist yarn, because the spun yarn brought to suchan untwisted state is returned to a state of raw cotton, and loses itsstrength as a yarn.

[0021] In view of the above, the present inventors further proceededwith a research in an attempt to produce a composite twist yarn having asuperior appearance and touch by securing entwining of a filament and aspun yarn. As a result of the research, they have found that making atwisted spun yarn and at least one filament parallel to each other to aparalleled yarn, twisting the paralleled yarn in a direction reverse tothe twisted direction of the spun yarn, and continuing the twisting ofthe paralleled yarn in the reverse direction over an untwisted point ofthe spun yarn is effective in producing a composite twist yarn havingsuperior properties with respect to all the features of texture,appearance, and touch, while securing strength as the spun yarn andentwining of the spun yarn and the filament, and thus, come up with thepresent invention.

[0022] As will be clearly described in the following, the compositetwist yarn produced according to the above technique has a unique twiststructure as compared with the conventional and known plied yarn in thatthe twisted direction of the composite twist yarn is substantiallyidentical to the twisted direction of the spun yarn in the compositetwist yarn, and that the number of twists of the composite twist yarn islarger than that of the spun yarn entwined in the composite twist yarn.

[0023] In the following, features of a twisting method unique to thepresent invention, and a composite twist yarn produced by the twistingmethod are described in detail referring to the drawings illustratingone embodiment of the present invention. It should be appreciated thatvarious changes and modifications will be apparent to those skilled inthe art. Therefore, unless otherwise such changes and modificationsdepart from the scope of the present invention hereinafter defined, theyshould be construed as being included therein.

[0024] According to the embodiment of the present invention, a singlespun yarn B which is twisted in a direction shown in FIG. 1 (Z-directionor Z-twist) and a filament M (monofilament or multifilament) arerendered parallel to each other to a paralleled yarn A, and theparalleled yarn A is twisted in a direction reverse to the Z-direction(namely, S-direction or S-twist), as shown in FIG. 2. As the paralleledyarn A is twisted in the S-direction, the spun yarn is graduallyuntwisted. As the paralleled yarn A is applied with S-twists by thenumber corresponding to the number of untwists of the spun yarn B, thefilament M is entwined around the spun yarn B.

[0025] As the paralleled yarn A is further twisted in the S-direction tosuch an extent that the number of S-twists corresponds to the number ofZ-twists which have been applied to the spun yarn B in its initial statebefore start of the S-twist, then, the spun yarn B is completelyuntwisted and rendered to an untwisted state. When the spun yarn B isbrought to the untwisted state, the spun yarn B is turned to a rawcotton state, and the strength as the spun yarn is lost. However,whereas the spun yarn B is rendered to such an untwisted state, thefilament M is entwined around the spun yarn B by the number of S-twistscorresponding to the number of Z-twists applied to the spun yarn B inthe initial state. Therefore, there is no likelihood that the spun yarnB in the untwisted state is loosened because the spun yarn B has itsouter portion securely entwined by the filament M.

[0026] In the above, the following should be considered. Since thestrength of the untwisted spun yarn B is substantially zero, thecomposite twist yarn relies its strength merely on the strength of thefilament M, and accordingly, a sufficient strength may not be secured.In view of this, according to the embodiment of the present invention,the paralleled yarn A is continued to be twisted in the reversedirection. As the paralleled yarn A is further twisted in the reversedirection, as shown in FIG. 4, the spun yarn B is twisted in thedirection (S-direction) reverse to the initially twisted direction(Z-direction). As the number of S-twists increases, the strength of thespun yarn B itself is recovered, and the filament M is further entwinedaround the spun yarn B, whereby the pitch of the S-twists of the twistyarn (namely, the composite twist yarn) A increases, and the strength ofthe composite twist yarn A increases. Thus, applying the S-twist to theparalleled yarn A to such an extent as to give a sufficient strength tothe spun yarn B over the untwisted state of the spun yarn B is effectivein providing the composite twist yarn with a sufficient strength.

[0027] Relations between changes in the twisted directions and thenumbers of twists with respect to the spun yarn B and the paralleledyarn A are as shown in FIG. 5. Specifically, referring to FIG. 5, arelation between a change in the twisted direction and the number oftwists of the paralleled yarn A is shown by the solid line X, and arelation between a change in the twisted direction and the number oftwists of the spun yarn B is shown by the solid line Y. It should benoted that Z-twist (e.g. 20 times per inch) has been applied to the spunyarn B in its initial state before making a paralleled yarn A. As theparalleled yarn A is twisted in the S-direction reverse to the initiallytwisted Z-direction of the spun yarn B, the paralleled yarn A is appliedwith the S-twist, as shown by the solid line Y accompanied by untwistingof the spun yarn B. When the spun yarn B is brought to an untwistedstate (see point Y₁), the paralleled yarn A is applied with S-twists(see point X₁) by the number substantially equal to the number ofZ-twists which have been applied to the spun yarn B in the initialstate.

[0028] Subsequently, as the S-twist is further applied to the paralleledyarn A, the spun yarn B is applied with the S-twist, opposite to theZ-twist which has been initially applied. As the S-twist is furthercontinued, the number of S-twists to the paralleled yarn A increases,accompanied by increase of the S-twists to the spun yarn B. When thespun yarn B reaches the point Y₂ (e.g. 20 times of S-twists per inch),the paralleled yarn A reaches the point X₂. At the point X₂, theparalleled yarn A is applied with the number of twists (namely, 40 timesper inch) which is equal to the sum of the number of twistscorresponding to the Z-twists (20 times per inch) which have beenapplied to the spun yarn B in the initial state and the number of twists(20 times per inch) which is additionally applied to the spun yarn Bfrom the untwisted state.

[0029] Accordingly, the inventive composite twist yarn which has reachedthe point X₂ is applied in its entirety with the S-twist, in which thetwisted direction of the inventive composite twist yarn is substantiallyidentical to the twisted direction of the spun yarn B entwined in thecomposite twist yarn. Thus, the resultant composite twist yarn has aunique twist structure in which the twisted direction of the compositetwist yarn is substantially identical to the twisted direction of thespun yarn B entwined therein, and the number of S-twists of thecomposite twist yarn is larger than that of the spun yarn entwined inthe composite twist yarn.

[0030] Although the twisted direction of the composite twist yarn as afinal product differs depending on the twisted direction of the spunyarn B in the initial state before the twisting process is initiated,according to the present invention, the twisted direction of thecomposite twist yarn as a final product is substantially identical tothe twisted direction of the spun yarn entwined in the composite spunyarn after the twisting process is terminated.

[0031] The numbers of twists of the composite twist yarn and the spunyarn entwined therein can be optionally varied by varying the number oftwists to be applied to the spun yarn B in the initial state and thenumber of twists to be applied to the composite twist yarn over theuntwisted state of the spun yarn B. Generally, the number of twists tobe applied to the spun yarn B in the initial state ranges from about 5to 45 times per inch depending on the count of the spun yarn B. Apreferred number of times of twists to be applied to the spun yarn Bafter the spun yarn B reaches the untwisted state generally ranges fromabout 5 to 45 times per inch in order to secure a strength inherent tothe spun yarn B. Therefore, the total number of twists to be applied tothe composite twist yarn as a final product ranges from about 5 to 90times per inch, and the number of twists to be applied to the spun yarnB entwined in the composite twist yarn ranges from about 5 to 45 timesper inch, which is about a half of the total number of twists to beapplied to the composite twist yarn.

[0032] More specifically, in case of a spun yarn B of the count No. 20,for example, the number of twists to be applied to the spun yarn B inthe initial state is generally in the range of 15 to 22 times per inch,most typically around 18 times per inch. A preferred number of twists tobe applied to the spun yarn B after the spun yarn B reaches itsuntwisted state is generally in the range of 15 to 22 times per inch(most typically, around 18 times per inch) to secure a strength inherentto the spun yarn B. Accordingly, the total number of twists to beapplied to the composite twist yarn as a final product is in the rangeof 30 to 44 times per inch (most typically, around 36 times per inch),and the number of twists to be applied to the spun yarn B entwined inthe composite twist yarn is in the range of 15 to 22 times per inch(most typically, around 18 times per inch), which is about a half of thetotal number of twists to be applied to the composite twist yarn.

[0033] In the embodiment of the present invention, since the strength ofthe composite twist yarn is remarkably increased by the increase of thenumber of twists of the filament, it may be possible to lessen thenumbers of twists of the composite twist yarn and the spun yarn B tofrom about 80 to 90% relative to the generally used respective numbersof twists thereof to secure a sufficient strength.

[0034] In the inventive composite twist yarn, there is a case that thenumber of twists of the composite twist yarn is remarkably larger thanthat of the spun yarn entwined therein. However, generally, the diameterof the filament to be entwined around the spun yarn is generallyremarkably smaller than that of the spun yarn. Accordingly, even if asmall-diametrical filament is tightly entwined around alarge-diametrical spun yarn, there is no likelihood that the spun yarnis excessively tightened by the filament, and the outer portion of thespun yarn in the composite twist yarn is sufficiently exposed whilebeing entwined by the filament. With this arrangement, the resultantcomposite twist yarn is provided with a texture, appearance, and touchsimilar to those of the core yarn, and a strength substantially equal tothat of the plied yarn. Further, according to the embodiment of thepresent invention, a single spun yarn is used. Accordingly, a compositetwist yarn of a fine count is easily produced, as compared with the caseof producing a plied yarn with use of two or three spun yarns.

[0035] As mentioned above, the inventive composite twist yarn has theunique twist structure obtained by implementing the unique twistingmethod. Specifically, the inventive composite twist yarn has thefeatures “the twisted direction of the composite twist yarn as a wholeis substantially identical to that of the spun yarn entwined in thecomposite twist yarn” and “the number of twists of the composite twistyarn is larger than that of the spun yarn entwined therein”. There is noconstraint regarding the material, size and the like of the spun yarnand the filament. All the kinds of spun yarns and filaments are usable.

[0036] Specifically, the spun yarn used in the present inventionincludes spun yarns such as all the kinds of plant fibers, animalfibers, regenerated fibers, and synthetic fibers, not to mention mosttypical spun yarns derived from cotton, hemp, and wool. Further, usableis a combined filament yarn, which is a combination of at least one ofthe aforementioned spun yarns and filaments. Generally, a synthetic orsemi-synthetic filament such as polyurethane, polyamide, polyester,acryl, and rayon is used as the filament in the present invention.Alternatively, a natural filament such as silk may be used. It isdesirable to use an elastic filament which has an elasticity of its ownsuch as a filament of a polyurethane resin in order to effectivelyutilize the property of the elastic filament in light of the fact thatthe core yarn and the plied yarn are frequently used as an elastic yarn.

[0037] According to the embodiment of the present invention, it isrequired to use a single spun yarn in order to effectively utilize thefeature of the abovementioned twisting process. Use of not less than onespun yarn may not be effective considering the feature of the presentinvention that an untwisted state of the spun yarn is utilized. The sizeof the spun yarn is not specifically limited. Any size of the spun yarnis selectable and usable depending on the use and purpose of use of theresultant composite twist yarn. It is desirable to select the number oftwists of the spun yarn depending on the count of the spun yarn. Thenumber of filaments is not specifically limited. One or more than onefilament (monofilament or multifilament) may be paralleled to a spunyarn to make a paralleled yarn. Generally, one or two filaments is used,and the size (denier) thereof can be optionally varied depending on theuse and purpose of use of the resultant composite twist yarn.

[0038] As mentioned above, a composite twist yarn of a fine count can beeasily produced by optionally adjusting the number of twists of thecomposite twist yarn produced by twisting a single spun yarn and atleast one filament together depending on the requirements on theresultant composite twist yarn.

[0039] The inventive composite twist yarn can be produced easily and ata low cost without the necessity of sorting out of raw cotton, which hasbeen required in the production of the conventional composite twistyarn, and yet exhibits superior texture, appearance, and touch similarto those of the expensive core yarn, and is usable for producingsophisticated woven and knitted fabrics.

[0040] The inventive composite twist yarn has the aforementionedfeatures. The features of the inventive composite twist yarn areeffectively exhibited in its use as a raw material yarn for variouswoven and knitted fabrics. The weaving pattern and knitting pattern withuse of the inventive composite twist yarn are not specifically limited.Any weaving pattern such as a plain weaving and a twill weaving areapplicable. In case of producing a woven fabric, the inventive compositetwist yarn may be used as either one of a warp yarn and a weft yarn, oras both of the warp yarn and the weft yarn. It is needless to say that awoven fabric can be produced by using the inventive composite twist yarnas part of a warp yarn and/or a weft yarn in combination with aconventional core yarn or the like.

[0041] In the case of a knitted fabric, the entirety of a knitted fabriccan be produced with use of the inventive composite twist yarn.Alternatively, a knitted fabric may be produced with partial use of theinventive composite twist yarn in combination with the other core yarnor the like.

[0042] Specifically, since the inventive composite twist yarn hassubstantially equivalent or superior properties to the conventional coreyarn, the features of the composite twist yarn are effectively exhibitedeven in a partial use thereof, not to mention its entire use forproducing a woven fabric or a knitted fabric. In view of this, althoughthe mixing ratio of the inventive composite twist yarn to the other kindof yarn is not specifically limited, the mixing ratio of the inventivecomposite twist yarn to the entirety of the yarns constituting a wovenfabric (knitted fabric) is preferably 20% or larger, more preferably 30%or larger, and furthermore preferably 50% or larger in order toeffectively utilize the features of the inventive composite twist yarn.

[0043] Use of the inventive composite twist yarn as, for example, a yarnfor a jeans fabric is preferable because the resultant jeans fabricexhibits a proper elasticity and flexibility.

[0044] As an example, the present inventors produced the followingcomposite twist yarn with use of a cotton spun yarn (cotton count No.20, 18 times of Z-twists per inch) and an elastic filament (under thetrade-name “espa”, product of Toyobo Co., Ltd.: 70 deniers, draft: 3.5times) at a mixing ratio of the cotton spun yarn to the elastic filamentof 93:7 (unit: %). The composite twist yarn was produced by making thecotton spun yarn and the elastic filament parallel to each other to aparalleled yarn, twisting the paralleled yarn in a direction reversed tothe twisted direction of the cotton spun yarn, and continuing thetwisting over the untwisted point of the cotton spun yarn up to a statewhere 18 times of S-twists per inch were applied to the cotton spunyarn. Thus, the composite twist yarn was applied with 36 times ofS-twists per inch, and the cotton spun yarn entwined in the compositetwist yarn was applied with 18 times of S-twists per inch.

[0045] The resultant composite twist yarn was bulky, exhibited anelasticity and a proper strength with the cotton spun yarn partlyappearing on the surface of the composite twist yarn and the elasticfilament being securely entwined around the cotton spun yarn. Thecomposite twist yarn exhibited desirable texture, appearance, and touchsimilar to those of a core yarn.

[0046] The present inventors woven a jeans fabric with use of the thusproduced composite twist yarn as a weft yarn and a cotton spun yarn ofthe count No. 7 as a warp yarn. The produced jeans fabric exhibitedsuperior appearance and touch with an elasticity in a transversedirection thereof being secured.

EXPLOITATION IN INDUSTRY

[0047] The present invention has the aforementioned arrangement, and isadvantageous in easily producing a composite twist yarn adapted forproducing a woven and knitted fabric substantially equivalent orsuperior to a conventional core yarn in appearance and touch. Theinventive method is advantageous in producing, with use of a twistingfacility easily and at a low cost, a composite twist yarn having asubstantially equivalent or superior quality to an expensive core yarnproduced by a complex spinning facility. The present invention does notrequire sorting out of cotton spun yarn material (removal of staples),which has been an essential step in producing a conventional core yarnin combined use of a cotton spun yarn. With the inventive method, acomposite twist yarn of a high quality can be produced at a low cost.Furthermore, according to the present invention, since a composite twistyarn of a fine count can be easily produced, applicability of theinventive composite twist yarn to a woven and knitted fabric can bebroadened.

1. A composite twist yarn comprising: a spun yarn and at least one filament, the spun yarn and the filament being twisted with each other, the twisted direction of the composite twist yarn being substantially identical to the twisted direction of the spun yarn entwined in the composite twist yarn, and the number of twists of the composite twist yarn being larger than the number of twists of the spun yarn entwined in the composite twist yarn.
 2. The composite twist yarn of claim 1, wherein the filament includes an elastic filament.
 3. A method for producing a composite twist yarn comprising the steps of: making a spun yarn twisted in one direction and at least one filament parallel to each other to produce a paralleled yarn; twisting the paralleled yarn in a direction reverse to the twisted direction of the spun yarn; and continuing the twisting in the reverse direction over an untwisted point of the spun yarn.
 4. The method of claim 3, wherein the filament includes an elastic filament.
 5. A woven fabric comprising at least part of a warp yarn and a weft yarn made of the composite twist yarn of any one of claims 1 and
 2. 6. A knitted fabric comprising at least part of a warp yarn and a weft yarn made of the composite twist yarn of any one of claims 1 through
 3. 